Passenger trains, particularly those for urban and suburban travel, are provided with sliding doors for closing the access passages leading to the inside of the trains. At present, a door of this type has a leaf which moves away from the passage, or two leaves which are placed side by side when in the closed position in front of the passage and which move away from each other towards their retracted position with one on each side of the passage.
To ensure sealing against wind, for example, as well as rain or pressure waves, the doors are provided with a sealing joint on their periphery. This sealing joint is pressed onto the outer surface of the flat wall of the vehicle at the edge of the passage when the door is in the closed position
When the door moves in a rectilinear way parallel to the flat wall of the vehicle, the joint remains in contact with this wall and rubs against it. The joint therefore rapidly deteriorates and the surface of the wall is degraded by the friction of the joint.
Some doors are mounted to be movable along the wall of the vehicle with a complex non-rectilinear movement which enables the door, when it is opened, to be initially moved away from the wall in order to detach the joint and then to be simply moved along the wall.
The means required to provide this movement of the door are relatively complicated and costly.
There are also known inflatable joints which expand when the door is in the closed position to bear on the wall, and which retract to move away from the wall when the door is to be opened. These joints are costly and must be formed from a flexible material which has poor vandal-resistance.